{"instruction": "You are an expert in named entity recognition. Please extract entities that match the schema definition from the input. Return an empty list if the entity type does not exist. Please respond in the format of a JSON string.", "schema": ["Chemical"], "input": "Nanocluster size is tuned from ~ 20 to ~ 40 nm by experimentally varying the final Au nanoparticle concentration and the polymer / Au ratio , along with the charge on the initial Au nanoparticle surface ."}
{"Chemical": ["Au"]}